Cut-off valve



(NoModel.) Gl V. P'UTMAN.

GUT-OFF VALVE.

No. 477,022. Patented June 14, 1892.

WITNESSES:

NVENTOR 2 ATTQRNEYS.

` UNITED STATES PATENT OFFICE.

GIDEON V. PUTMAN, OF GLOVERSVILLE, NE\V YORK.

f CUT-OFF VALVE.

SPECIFICATION forming part of Letters Patent No. 477,022, dated June 14,1892.'

Application filed October 24, 1891. Serial No. 409,705. (No model.)

To aZZ whom t may concern.-

Be it known that I, GIDEON V. PUTMAN, of Gloversville, in the county ofFulton, in the State of New York, have invented new and usefulImprovements in Cut-@ff Valves for Steam-Engines, of which thefollowing, taken inconnection with the accompanying drawings, is a full,clear, and exact description.

rlhis invention relates to a cut-off Valve adapted to be used onstationary engines as well as on locomotives; and the invention consistsin a novel construction of said cut-off valve whereby the same isrendered very sensitive and very efficient in its operation, all ashereinafter more fully described, and set forth in the claims.

In the annexed drawings, Figure l is a side view illustrating one of themodes of applying my improved cut-off valve to a stationary engine. Fig.2 is an enlarged longitudinal section of the cut-olf valve, and Fig. 3is a transverse section on line m in Fig. 2.

Similar letters of reference indicate corresponding parts.

A represents the steam-chest of the cut-olf valve, which steam-chest Ipreferably make of cylindrical form, as shown. It is secured either tothe top or side of the main-valve steam-chest C, which is provided withthe usual valve by which steam is admitted to and emitted from thecylinder D of the engine in the usual and Well-known manner,

' not necessary to be here illustrated.

P denotes the steam-pipe, by which live steam is admitted into thecut-off-valve chest A, which is provided in its side with two steamportsa a, by which it communicates with the interior of the main-valvesteam-chest C. In the chest A are arranged two cylindricalthrottling-slides ZJ ZJ, which are of the same or nearly the samediameter as the interior of said chest and movable toward and from eachother. Each of said slides is provided With a steam-port c in the sideadjacent to the ports a a and a suiicient distance from the inner end orend adjacent to the companion slide to form a bridge CZ. Each of thesethrottlingslides has attached to it a separate rod e, and the two rodsextend through one and the same end of the chest A and are connected toopposite ends of a centrally pivoted lever Z.,

The pivotal support may be a bracket Z on the governorstand7 as shown.Then the throttle-valve is applied to a stationary engine, the saidlever is suitably arranged to be operated by a suitable governor g,driven by the engine; but when connected to a locomotive the lever Z isto be operated by another lever suitably connected thereto and undercontrol of the engineer. By operating the lle- .ver Z the twothrottling-slides are caused to move either toward or from each other,and thus carry the ports c c of said slides to a greater or less degreein or out of communication with `the ports a c of the chest A, andconsequently the admission of steam to the main-valve steam-chest isvaried in volume. This is effected automatically by the governor g,which. in its dormant position holds the lover Z so as to cause thethrottling-slides bb to stand with their ports c c directly over theports a a of the chest A, and when the engine is in motion the governorg turns the lever Z so as to carry the throttling-slides toward oppositeends of the chest A to a greater or less distance, according to thevelocity of the governor, and said movement of the throttlingslidescarries the ports thereof to a correspending degree out of communicationwith the ports a a, the steam being thereby cut off or partly cut offfrom the main-valve steamchest and the speed of the engine is checked.Within the throttling-slides is located a cylindrical slide-valve f,preferably composed of two cylinders rigidly secured to one and the samestem f and a proper distance apart to form between them a steam-port t'of about the same width as the bridge a between the ports a c of thechest A. The valve-stem f extends through the end of the chest A, and isconnected te an eccentric secured to the main shaft or crankshaft o ofthe engine. The connection of the stein f with the said eccentric may bemade in various ways, one

of which is indicated by the lever p and eccentric-rod 1f in Fig. l ofthe drawings. The

`valve f thus has a uniform stroke, and the throttling of the steam iseffected by the movement of the slides b ZJ.

In order to balance the described throttlen valve, I form the interiorof the chest A with circumferential grooves r r in line with the IOOports a a to allow the steam to circulate between the slides and valvef, and I perforate the heads of the throttling-slides b I) and also thediaphragms s s of the valvef, to which the stem f is attached, to allowsteam to pass to the ends of the chest A. The pressure of the steam onthe throttling-slides and cut-off valve is thus equalized as near aspossible, and consequently wear and tear is greatly obviated.

Having described my invention, What I claim as new, and desire to secureby Letters Patent, is-

1. In combination with the main valve steam-chest of an engine, acutoff-valve chest vreceiving the live steam and provided withstean1-po1ts communicating with said steamchest, throttling-slidesseated movably toward and from each other Within the cut off-valve chestand provided with steam ports and bridges at their adjacent ends, rodsextending from the throttlingslides, a centrallypivoted lever connectedat opposite ends to said rods to regulate the throttling, and a cutoltvalve placed movably over the ports of the throttling-slides andactuated by the motion of the engine, as set forth.

2. In combination with the main valve Steam-chest of an engine, acut-ott-valve chest of' cylindrical form receiving the live steam andhaving in its side steam-ports communicating with the mainstealnchest,two cylindrical throttling-slides in said cut-oit-valvechest and of the same or nearly the same diameter and provided each witha steam-port in its side and with a bridge at its inner end, two rodsextending, respectively, from the two throttling-slides through one andthe same end of the cut-oit-valve chest, acentrally-pivoted leverconnected at opposite ends to the said rods to move the slidessimultaneously in opposite directions, a governor actuating said lever,a cylindrical slide-valve located in the throttling-slides and providedin its side With a port of about the same Width as the bridge betweenthe ports of the cut-off-valve chest, anda rod extending from said valvethrough the end ot` said chest and receiving reciprocating motion fromthe engine, as set forth.

3. The combination of the cut-ot-valve chest A ot' cylindrical t'orm'and provided with the ports a a and circumferential grooves r fr, thecylindrical throttling-slides b b, having perforated heads, and thevalve f, having perforated diaphragms s s, substantially as describedand shown.

In testimony whereof I have hereunto signed my name this 19th day ofOctober, 1891.

GIDEON V. PUTMAN. [L s] Witnesses:

L. CATEN, LYMAN K. BROWN.

